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1.
多相混输泵输送技术在油田的应用 总被引：1，自引：0，他引：1
多相混输泵输送技术是近几年发展较快的一项新技术，概述了混输泵应用的意义及试验情况，对混输泵试验的结果及设计安装中的有关问题进行了分析和讨论，，介绍了多相混输泵现场应用效果和经验。 相似文献
2.
Real-time controlled pesticide application requires a fast reacting system, enabling continuous variation of pesticide type and concentration based on a control signal. Direct injection systems meet the requirements for such application; however there are significant differences in the response time and quality of single system designs. This article discusses the complex of problems in direct injection systems in connexion with real-time control and proposes optimisations of system parts in order to reduce the response time and improve the quality of the process. The system response time was reduced to 160 ms for 1% output concentration by optimization of the control process, injection assembly and mixing chamber design. 相似文献
3.
基层农机推广工作简论 总被引：1，自引：1，他引：0
结合彰武县农业机械推广工作的实践,从经费筹集、体系建设、科技创新、服务内容4个方面,详细介绍搞好县级以下基层农机推广工作的建议和措施,以期为农机推广工作提供有益参考。 相似文献
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以某型号连杆为例,在hypermesh中对连杆模型进行了网格划分,对划分好的有限元模型导入到abaqus中进行计算,在既定工况得到连杆的应力及变形等,通过分析表明该连杆满足设计需求。 相似文献
6.
高端人才的缺乏以及人才素质问题已经成为制约辽宁科技特派行动的主要因素。分析科技特派行动高端人才支撑体系在运行机制、体系构建及内外部协调等方面存在的问题,提出具体的完善措施。 相似文献
7.
We developed a methodological protocol for comprehensive evaluation of nutrient management (NM) technologies for production of cauliflower taking its yield, quality, profitability, energy balance and environmental sustainability in terms of soil quality as the goal variables. Fifteen NM technologies comprising three sources of nutrients viz., organics [farmyard manure (FYM), vermicompost (VC) and green manure], inorganic fertilizations (recommended NPK at the rate of 200-44-82 kg ha−1and 125% of recommended NPK) and their selected combinations were tested for producing cauliflower for six consecutive growing seasons during 2006–2011. Integrated NM technology proved to be economically sound and environment-friendly practice. It helped to produce better quality cauliflower with higher value added products such as crude protein, dietary fibre, and vitamin C. Further, it concomitantly maintained better soil quality by improving soil organic carbon stock, microbial biomass carbon, bulk density and extractable plant available nutrients. Combining all the parameters together by employing non-parametric evaluation of regression factor scores through principal component analysis, the NM technology of FYM 5 Mg ha−1 + 125% of recommended NPK and VC 3 Mg ha−1 + 125% of recommended NPK were found to be the best among the NM technologies compared. The superiority of the technologies were attributed to higher curd biomass yield (8.36 and 9.70 Mg ha−1, respectively), higher economic return (benefit-cost ratio 2.7 and 2.5; marginal rate of return 8.0 and 5.1, respectively), more energy conserving efficiency (net energy 22.4 and 25.7 GJ ha−1; output-input energy ratio 1.86 and 2.00, respectively) and greater improvement in the indices of soil quality (6.219 and 5.709, respectively) and crop quality for human (6.7 and 7.4, respectively) and animal (7.4 and 6.4, respectively) nutrition. Organics were less productive, less profitable, and energetically less efficientas compared to integrated and inorganic systems for cauliflower production in subtropics. 相似文献
8.
Because of the relative dearth of scientific information in agroforestry, monitoring and evaluation of agroforestry technologies in development projects plays an important role in the development and improvement of technical extension recommendations. To identify appropriate methodologies, ICRAF conducted in 1988–89 a review of agroforestry technology monitoring and evaluation in 166 projects worldwide, of which 108 responded. Almost 80% of these were involved in technology evaluation. Many extension projects were conducting research to test technologies on-farm or on research plots. Technology evaluation by projects focused on the biological of trees, often with inadequate consideration of the technology context. Few projects seemed to use farmer assessment in evaluation. Recommendations are made for an effective evaluation process and selection of appropriate methods and variables to be assessed by projects. Methods should be selected according to the availability of resources and should favour collaborative or collegial interaction between farmers and project staff. 相似文献
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10.
食品工艺实验教学方法的研究与实践 总被引：1，自引：0，他引：1
食品工艺实验教学是食品工艺学教学中重要的实践性教学环节。为了提高食品工艺学实验课的教学质量,采用设计性实验教学模式,对传统的食品工艺教学方法实施改革。实施效果表明,开设设计性实验,得到学生普遍认同,这种教学培养了学生的学习兴趣和团队精神,提高了学生综合实验技能、动手能力、创新精神,以及分析问题和解决问题的能力。 相似文献